In the aftermath of WW2, the war crimes of common Russian soldiers was well documented, most infamously in Berlin. Rape and murder was absolutely rife, civilians were even found crucified in some cases.

Western WW2 historians have no reason to lie about this, as Russia was one of the Allies. If anything they have every reason to cover it up and down play it, which many historians do. They often try to justify it by saying that Russian civilians had also been brutalized by German soldiers therefore it was understandable. This sort of apologist mentality for Russian war crimes is extremely common with American and British WW2 historians.

The fact is committing war crimes like this is part of the M.O. of the Russian army, their commanders and general military culture seems to actively encourage it.

And the WW2 war crimes were committed when the Russians were the victors, so God knows the level of vengeance they'd exact on the civilian population when they're losing.

Saying that Russian war crimes in Ukraine are all faked makes no sense, as in reality it fits historic descriptions of the conduct of the Russian army very accurately.